include/wx/wxexpr.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wxexpr.h
   3 // Purpose:     Prolog-like file I/O, used by resource system.
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     01/02/97
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c)
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_WXEXPRH__
  13 #define _WX_WXEXPRH__
  14
  15 #ifdef __GNUG__
  16 #pragma interface "wxexpr.h"
  17 #endif
  18
  19 #include <stdio.h>
  20
  21 #include "wx/defs.h"
  22 #include "wx/string.h"
  23
  24 #if USE_IOSTREAMH
  25 #include <iostream.h>
  26 #else
  27 #include <iostream>
  28 #endif
  29
  30 #include "wx/list.h"
  31 #include "wx/hash.h"
  32
  33 #include "wx/expr.h"
  34
  35 // Compatibility
  36 #define PrologExpr wxExpr
  37 #define PrologDatabase wxExprDatabase
  38 #define proioErrorHandler wxExprErrorHandler
  39 #define PROIO_ERROR_GENERAL 1
  40 #define PROIO_ERROR_SYNTAX  2
  41 #define PrologNull wxExprNull
  42 #define PrologInteger wxExprInteger
  43 #define PrologReal wxExprReal
  44 #define PrologWord wxExprWord
  45 #define PrologString wxExprString
  46 #define PrologList wxExprList
  47 #define PrologType wxExprType
  48
  49 // Error types
  50 #define WXEXPR_ERROR_GENERAL 1
  51 #define WXEXPR_ERROR_SYNTAX  2
  52
  53 // Error handler function definition. If app returns TRUE,
  54 // carry on processing.
  55 typedef bool (*wxExprErrorHandler) (int errorType, char *msg);
  56
  57 WXDLLEXPORT_DATA(extern wxExprErrorHandler) currentwxExprErrorHandler;
  58
  59 WXDLLEXPORT_DATA(extern "C" FILE*) yyin;
  60
  61 extern "C" int WXDLLEXPORT yyparse(void);
  62
  63 typedef enum {
  64     wxExprNull,
  65     wxExprInteger,
  66     wxExprReal,
  67     wxExprWord,
  68     wxExprString,
  69     wxExprList
  70 } wxExprType;
  71
  72 class WXDLLEXPORT wxExprDatabase;
  73
  74 class WXDLLEXPORT wxExpr
  75 {
  76  public:
  77   wxObject *client_data;
  78   wxExprType type;
  79   union {
  80     long integer;
  81     char *word;
  82     char *string;
  83     double real;
  84     wxExpr *first;  // If is a list expr, points to the first node
  85     } value;
  86
  87   wxExpr *next;     // If this is a node in a list, points to the next node
  88   wxExpr *last;     // If is a list expr, points to the last node
  89
  90   wxExpr(wxExprType the_type, char *word_or_string, bool allocate);
  91   wxExpr(const wxString& functor);      // Assume this is a new clause - pass functor
  92   wxExpr(wxExprType the_type, const wxString& word_or_string = "");
  93   wxExpr(long the_integer);
  94   wxExpr(double the_real);
  95   wxExpr(wxList *the_list);
  96   ~wxExpr(void);
  97
  98   inline wxExprType Type(void) const { return type; }
  99   inline long IntegerValue(void) const
 100   {
 101     if (type == wxExprInteger)
 102       return value.integer;
 103     else if (type == wxExprReal)
 104       return (long)value.real;
 105     else return 0;
 106   }
 107
 108   inline double RealValue(void) const {
 109     if (type == wxExprReal)
 110       return value.real;
 111     else if (type == wxExprInteger)
 112       return (double)value.integer;
 113     else return (double)0.0;
 114   }
 115
 116   inline wxString WordValue(void) const {
 117     if (type == wxExprWord)
 118       return value.word;
 119     else if (type == wxExprString)
 120       return wxString(value.string);
 121     else return wxString("");
 122   }
 123
 124   inline wxString StringValue(void) const {
 125     if (type == wxExprString)
 126       return wxString(value.string);
 127     else if (type == wxExprWord)
 128       return wxString(value.word);
 129     else return wxString("");
 130   }
 131
 132   // Get nth arg of clause (starting from 1)
 133   wxExpr *Arg(wxExprType type, int arg) const;
 134
 135   // Return nth argument of a list expression (starting from zero)
 136   wxExpr *Nth(int arg) const;
 137
 138   // Returns the number of elements in a list expression
 139   int Number(void) const;
 140
 141   // Make a clone
 142   wxExpr *Copy(void) const;
 143
 144   wxExpr *GetAttributeValueNode(const wxString& word) const;  // Use only for a clause or list
 145   wxExpr *AttributeValue(const wxString& word) const;  // Use only for a clause
 146   wxString Functor(void) const;                     // Only for a clause
 147   bool IsFunctor(const wxString& s) const;                     // Only for a clause
 148   void WriteClause(ostream& stream);  // Write this expression as a top-level clause
 149   void WriteExpr(ostream& stream);    // Write as any other subexpression
 150   void WriteLispExpr(ostream& stream);
 151
 152   // Append an expression to a list
 153   void Append(wxExpr *expr);
 154   // Insert at beginning of list
 155   void Insert(wxExpr *expr);
 156
 157   // Get first expr in list
 158   inline wxExpr *GetFirst(void) const { return ((type == wxExprList) ? value.first : (wxExpr*)NULL); }
 159
 160   // Get next expr if this is a node in a list
 161   inline wxExpr *GetNext(void) const { return next; }
 162
 163   // Get last expr in list
 164   inline wxExpr *GetLast(void) const { return ((type == wxExprList) ? last : (wxExpr*)NULL); }
 165
 166   // This should really be called SetAttributeValue since any existing
 167   // attribute-value is deleted first.
 168   void AddAttributeValue(const wxString& attribute, long value);
 169   void AddAttributeValue(const wxString& attribute, double value);
 170   void AddAttributeValueWord(const wxString& attribute, const wxString& value);
 171   void AddAttributeValueString(const wxString& attribute, const wxString& value);
 172   void AddAttributeValue(const wxString& attribute, wxList *value);
 173   void AddAttributeValue(const wxString& attribute, wxExpr *value);
 174   void AddAttributeValueStringList(const wxString& attribute, wxList *string_list);
 175
 176   void DeleteAttributeValue(const wxString& attribute);
 177
 178   bool GetAttributeValue(const wxString& att, int& var) const;
 179   bool GetAttributeValue(const wxString& att, long& var) const;
 180   bool GetAttributeValue(const wxString& att, float& var) const;
 181   bool GetAttributeValue(const wxString& att, double& var) const;
 182   bool GetAttributeValue(const wxString& att, wxString& var) const;  // Word OR string -> string
 183   bool GetAttributeValue(const wxString& att, wxExpr **var) const;
 184
 185   // Compatibility with old PrologIO
 186   inline void AssignAttributeValue(char *att, int *var) const { GetAttributeValue(att, *var); }
 187   inline void AssignAttributeValue(char *att, long *var) const { GetAttributeValue(att, *var); }
 188   inline void AssignAttributeValue(char *att, float *var) const { GetAttributeValue(att, *var); }
 189   inline void AssignAttributeValue(char *att, double *var) const { GetAttributeValue(att, *var); }
 190   inline void AssignAttributeValue(char *att, wxExpr **var) const { GetAttributeValue(att, var); }
 191   void AssignAttributeValue(char *att, char **var) const ;  // Word OR string -> string
 192
 193   // Add string items to list if the list attribute exists
 194   bool GetAttributeValueStringList(const wxString& att, wxList *var) const;
 195
 196   // Associate other data with this expression, e.g. when reading in a
 197   // number of linked items - store C++ object pointer with the expression
 198   // so we can index into the wxExpr database and fish out the pointer.
 199   inline void SetClientData(wxObject *data) { client_data = data; }
 200   inline wxObject *GetClientData(void) const { return client_data; }
 201 };
 202
 203 class WXDLLEXPORT wxExprDatabase: public wxList
 204 {
 205   DECLARE_DYNAMIC_CLASS(wxExprDatabase)
 206  private:
 207   wxNode *position;              // Where we are in a search
 208   wxHashTable *hash_table;
 209   wxString attribute_to_hash;
 210  public:
 211   int noErrors;
 212
 213   wxExprDatabase(wxExprErrorHandler handler = 0);
 214
 215   // Use hashing on both the functor, and the attribute of
 216   // specified type (wxExprString or wxExprInteger) and name.
 217   // So to find node 45
 218   // (i.e. match the clause node(id=45, ...))
 219   // it usually requires 1 look-up: the keys for functor and attribute
 220   // are added together.
 221   // Obviously if the attribute was missing in a clause, it would
 222   // fail to be found by this method, but could be retrieved by a
 223   // linear search using BeginFind and FindClauseByFunctor,
 224   // or just searching through the list as per usual.
 225
 226   wxExprDatabase(wxExprType type, const wxString& attribute, int size = 500,
 227                  wxExprErrorHandler handler = 0);
 228
 229   ~wxExprDatabase(void);
 230
 231   void BeginFind(void) ;          // Initialise a search
 232   wxExpr *FindClause(long id) ;  // Find a term based on an integer id attribute
 233                                  // e.g. node(id=23, type=rectangle, ....).
 234
 235   // Find on basis of attribute/value pairs, e.g. type=rectangle
 236   // This doesn't use hashing; it's a linear search.
 237   wxExpr *FindClause(const wxString& word, const wxString& value);
 238   wxExpr *FindClause(const wxString& word, long value);
 239   wxExpr *FindClause(const wxString& word, double value);
 240   wxExpr *FindClauseByFunctor(const wxString& functor);
 241
 242   wxExpr *HashFind(const wxString& functor, const wxString& value) const;
 243   wxExpr *HashFind(const wxString& functor, long value) const;
 244
 245   void Append(wxExpr *expr);  // Does cleverer things if hashing is on
 246   void ClearDatabase(void);
 247   inline int GetErrorCount() const { return noErrors; }
 248   bool Read(const wxString& filename);
 249   bool ReadFromString(const wxString& buffer);
 250   bool Write(const wxString& fileName);
 251   bool Write(ostream& stream);
 252   void WriteLisp(ostream& stream);
 253
 254   // Compatibility
 255   inline bool ReadProlog(char *filename) { return Read(wxString(filename)); }
 256   inline bool ReadPrologFromString(char *buffer) { return ReadFromString(wxString(buffer)); }
 257   inline void WriteProlog(ostream& stream) { Write(stream); }
 258 };
 259
 260 // Function call-style interface - some more convenience wrappers/unwrappers
 261
 262 // Make a call
 263 wxExpr* WXDLLEXPORT wxExprMakeCall(const wxString& functor ...);
 264
 265 #define wxExprMakeInteger(x) (new wxExpr((long)x))
 266 #define wxExprMakeReal(x) (new wxExpr((double)x))
 267 #define wxExprMakeString(x) (new wxExpr(wxExprString, x))
 268 #define wxExprMakeWord(x)   (new wxExpr(wxExprWord, x))
 269 #define wxExprMake(x)       (new wxExpr(x))
 270
 271 // Checks functor
 272 bool WXDLLEXPORT wxExprIsFunctor(wxExpr *expr, const wxString& functor);
 273
 274 // Temporary variable for communicating between wxexpr.cpp and YACC/LEX
 275 WXDLLEXPORT_DATA(extern wxExprDatabase*) thewxExprDatabase;
 276
 277 // YACC/LEX can leave memory lying around...
 278 extern "C" int WXDLLEXPORT wxExprCleanUp();
 279
 280 #endif
 281